Chlorhexidine-induced gastritis

Anti-Candida activity and in vitro toxicity screening of antifungals complexed with β-cyclodextrin

The emergence of resistant fungal species and the toxicity of currently available antifungal drugs are relevant issues that require special consideration. Cyclodextrins inclusion complexes could optimize the antimicrobial activity of such drugs and create a controlled release system with few side effects. This study aimed to assess the in vitro toxicity and antifungal effectiveness of nystatin (Nys) and chlorhexidine (Chx) complexed or not with β-cyclodextrin (βCD). First, a drug toxicity screening was performed through the Artemia salina bioassay. Then, the minimum inhibitory concentrations (MICs) against Candida albicans were determined with the broth microdilution test. After MICs determination, the cytotoxicity of the drugs was evaluated through the methyl-thiazolyl-tetrazolium (MTT) and neutral red (NR) assays and through cell morphology analysis. The PROBIT analysis was used to determine the median lethal concentration (LC50), and the cell viability values were submitted to one-way analysis of variance(ANOVA)/Tukey (α = 0.05). Overall, the βCD-complexed antifungals were less toxic against A. salina than their raw forms, suggesting that inclusion complexes can reduce the toxicity of drugs. The MICs obtained were as follows: Nys 0.5 mg/L; Nys:βCD 4 mg/L; Chx 4 mg/L; and Chx:βCD 8 mg/L. Chx showed significant cytotoxicity (MTT: 12.9 ± 9.6%; NR: 10.6 ± 12.5%) and promoted important morphological changes. Cells exposed to the other drugs showed viability above 70% with no cellular damage. These results suggest that antifungals complexed with βCD might be a biocompatible option for the treatment of Candida-related infections.

Inhibition of streptococcal biofilm formation by Aronia by extracellular RNA degradation

BACKGROUND

The accumulation of oral bacterial biofilms is one of the primary etiological factors for oral diseases. Aronia melanocarpa extracts display general health benefits, including antimicrobial activities. This study evaluates the inhibitory effect of Aronia juice on oral streptococcal biofilm formation.

RESULTS

Exposure to 1/10-diluted Aronia juice for 1 min significantly decreased in vitro streptococcal biofilm formation (P < 0.001). No remarkable difference was noted in streptococcal growth by Aronia under the same conditions. Interestingly, 1 week of oral rinse with diluted Aronia juice led to significantly fewer salivary streptococcal colony-forming units (CFUs) relative to oral rinsing with tap water (P < 0.05). Furthermore, Aronia exerted an extracellular RNA-degrading effect, and RNase inhibitor alleviated Aronia-dependent streptococcal biofilm inhibition.

CONCLUSION

Aronia might inhibit initial biofilm formation by decomposing extracellular RNA, which plays an important role in bacterial biofilm formation. Our data suggest that oral rinsing with Aronia juice will aid in treating oral biofilm-dependent diseases easily and efficiently. © 2019 Society of Chemical Industry.

Inhibition of streptococcal biofilm by hydrogen water

OBJECTIVES

The accumulation of oral bacterial biofilm is the main etiological factor of oral diseases. Recently, electrolyzed hydrogen-rich water (H-water) has been shown to act as an effective antioxidant by reducing oxidative stress. In addition to this general health benefit, H-water has antibacterial activity for disease-associated oral bacteria. However, little is known about the effect of H-water on oral bacterial biofilm. The objective of this study was to confirm the effect of H-water on streptococcal biofilm formation.

METHODS

In vitro streptococcal biofilm was quantified using crystal violet staining after culture on a polystyrene plate. The effect of H-water on the expression of genes involved in insoluble glucan synthesis and glucan binding, which are critical steps for oral biofilm formation, was evaluated in MS. In addition, we compared the number of salivary streptococci after oral rinse with H-water and that with control tap water. Salivary streptococci were quantified by counting viable colonies on Mitis Salivarius agar-bacitracin.

RESULTS

Our data showed that H-water caused a significant decrease in in vitro streptococcal biofilm formation. The expression level of the mRNA of glucosyltransferases (gtfB, gtfc, and gtfI) and glucan-binding proteins (gbpC, dblB) were decreased remarkably in MS after H-water exposure for 60s. Furthermore, oral rinse with H-water for 1 week led to significantly fewer salivary streptococci than did that with control tap water.

CONCLUSIONS

Our data suggest that oral rinse with H-water would be helpful in treating dental biofilm-dependent diseases with ease and efficiency.

Chlorhexidine - Pharmacology and Clinical Applications

chlorhexidine is a widely used skin antisepsis preparation and is an ingredient in toothpaste and mouthwash. It is an especially effective antiseptic when combined with alcohol. Its antimicrobial effects persist because it is binds strongly to proteins in the skin and mucosa, making it an effective antiseptic ingredient for handwashing, skin preparation for surgery and the placement of intravascular access. Catheters impregnated with chlorhexidine and antimicrobial agents can reduce the incidence of catheter-related bloodstream infections. Contact dermatitis related to chlorhexidine is not common in health care workers. The incidence of contact dermatitis to chlorhexidine in atopic patients is approximately 2.5 to 5.4%. Acute hypersensitivity reactions to chlorhexidine are often not recognised and therefore may be underreported. This review discusses the pharmacology, microbiology, clinical applications and adverse effects of chlorhexidine.

Poisoning due to Savlon (cetrimide) liquid

1. Seven adult cases of deliberate oral exposure to 'Savlon' liquid (chlorhexidine gluconate 0.3%, cetrimide 3%) are presented. 2. In six patients, the symptoms were relatively mild including nausea, vomiting, sore throat and abdominal pain. 3. One patient who had concomitantly taken 'Dettol' liquid was comatose and hypotensive at presentation and was complicated by aspiration pneumonia and adult respiratory distress syndrome (ARDS). She was ventilated for a total of 10 days and was hospitalised for 5 weeks. 4. The data from this study suggest that symptoms associated with Savlon poisoning are usually mild. When aspirated, Savlon together with 'Dettol' liquid can cause ARDS.